Graphics input or output devices are well known in the art. One such device employing a linear array of photodiode sensors is commercially available from "Reticon" of Sunnyvale, Calif.
This array of photodiodes is positioned so that light impinging upon a document to be copied forms an image on the array through a suitable lens system. The document is moved by a control mechanism which synchronously strobes the array to provide signals representative of the linear image segment being scanned.
A problem with this type of arrangement is that a considerable distance is required between the array and the document in order to reduce the scanned image to a size compatible with the minute size of the array. Further, all the sensors have to be perfect and the signals provided by the array require additional means to store and convert the signals to digital form.
Graphic devices are known which employ fiber optic bundles to permit segments of a scanned image to be applied to minute sensor arrays without the considerable distance previously required. The signal output of such a fiber optic bundle still requires conversion to digital form and the fiber bundle has to provide physical coherence between the input and output (picture elements or pixels) such that the relationships between the signals at the input ends of the fibers and at the output ends of fibers are identical. The term "physical coherence" means that those relationships are maintained physically by keeping the fibers at the output end in a predetermined physical relationship with respect to the fibers at the input end. The requirement of coherence in a bundle of so many fibers of such small size is difficult to achieve and, therefore, costly.